In a wireless telecommunications network, radio base stations are in radio communication with mobile terminals within their predefined coverage area or cell. Consequently, the continued operation of base stations are essential for providing mobile terminals access to the telecommunications network. For this reason, it is desirable for base stations to remain operational in spite of the many types of problems that may occur. For example, when considering power failures, having a backup power source becomes an important consideration when installing the infrastructure for the base stations.
Suitable exemplary backup power sources may include batteries, which are typically bulky and costly, or diesel electric generators. These backup power sources provide replacement power whenever the primary power source fails.
A factor that can significantly impact the ability of base stations to function is the operating temperature of the equipment. Therefore, many installation sites incorporate carefully controlled temperature environments in order to prevent equipment failure due to overheating. The type of cooling methods employed at these sites may ranges from using air conditioned rooms to elaborate heat removal devices such as water tanks, to simple air ventilation. But there are problems associated with many of these cooling solutions. For example, the high expense of obtaining backup power for radio base stations results in the lack of provisioning power to the air conditioning unit while operating in backup mode. To illustrate the amounts of power necessary, a typical three sectored base station site having 24 transceivers per sector transmitting at 30 watts requires approximately 11.9 kilowatts of power. What's more, a similar amount heat dissipation is required thereby placing more importance on cooling means. Since many backup systems are required to power base stations for at least 2-4 hours or more, extraneous power consuming equipment such as air conditioners are often sacrificed. Without cooling means, a base station would rapidly generate excessive heat to levels that may lead to equipment failure.
In an effort to reduce costs, some base stations are housed in simple low cost shelters. These shelters are relatively small and austere structures that provide little more than basic protection from the environment. Shelters and also small equipment rooms will cause a very fast increase of the temperature due to the small volume. As a further example, the disadvantage of the water tank method is that it tends to be expensive and space intensive. Also, the use of simple air ventilation is not adequate since they typically only work efficiently with relatively cool outside temperatures.
In view of the foregoing, it is an objective of the present invention to provide a method of maintaining base station operations by controlling the excessive heat generated by the base station equipment.